//
// ply2bin - Convert ASCII PLY file to binary PLY
// Programmed and designed by Matti 'ccr' Hämäläinen <ccr@tnsp.org>
// (C) Copyright 2019 Tecnic Software productions (TNSP)
//
// See file "COPYING" for license information.
//
#include <SDL.h>

// Get rid of the SDL_main mess for some commandline tools
#define _SDL_main_h
#define SDL_main main

#include "dmutil.h"
#include "dmmodel.h"


bool dmFWriteFloatLE(FILE *fh, const float val)
{
    float tmp = SDL_SwapFloatLE(val);
    return fwrite(&tmp, sizeof(tmp), 1, fh) == 1;
}


bool dmFWriteU32LE(FILE *fh, const Uint32 val)
{
    Uint32 tmp = SDL_SwapLE32(val);
    return fwrite(&tmp, sizeof(tmp), 1, fh) == 1;
}


bool dmFWriteU8(FILE *fh, const Uint8 val)
{
    return fwrite(&val, sizeof(val), 1, fh) == 1;
}


bool dmFWriteBINPLY(FILE *fh, const DMModel &model)
{
    bool writeNormals = model.normals.size() == (unsigned int) model.nvertices;

    fprintf(fh,
    "ply\n"
    "format binary_little_endian 1.0\n"
    "element vertex %d\n"
    "property float x\n"
    "property float y\n"
    "property float z\n",
    model.nvertices);

    if (writeNormals)
    {
        fprintf(fh,
        "property float nx\n"
        "property float ny\n"
        "property float nz\n"
        );
    }

    fprintf(fh,
    "element face %d\n"
    "property list uchar uint vertex_indices\n"
    "end_header\n",
    model.nfaces);

    for (int nvert = 0; nvert < model.nvertices; nvert++)
    {
        const DMVector3 &vert = model.vertices[nvert];

        if (!dmFWriteFloatLE(fh, vert.x) ||
            !dmFWriteFloatLE(fh, vert.y) ||
            !dmFWriteFloatLE(fh, vert.z))
                return false;

        if (writeNormals)
        {
            const DMVector3 &vert = model.normals[nvert];
            if (!dmFWriteFloatLE(fh, vert.x) ||
                !dmFWriteFloatLE(fh, vert.y) ||
                !dmFWriteFloatLE(fh, vert.z))
                return false;
        }
    }

    for (int nface = 0, offs = 0; nface < model.nfaces; nface++)
    {
        if (!dmFWriteU8(fh, 3))
            return false;

        for (int nvert = 0; nvert < 3; nvert++)
        {
            if (!dmFWriteU32LE(fh, model.faces[offs++]))
                return false;
        }
    }

    return true;
}


int main(int argc, char *argv[])
{
    bool
        optShowHelp = false;
    std::string optInputFilename, optOutputFilename;
    FILE *outFile = NULL;
    DMModel model;

    // Check commandline argument for enabling shaders
    for (int narg = 1; narg < argc; narg++)
    {
        char *arg = argv[narg];
        if (arg[0] == '-')
        {
            char *opt = arg + 1;

            if ((opt[0] == '-' && opt[1] == 'h' && opt[2] == 'e') ||
                opt[0] == '?' || (opt[0] == '-' && opt[1] == '?'))
            {
                optShowHelp = true;
                break;
            }
            else
            if (opt[0] == '-')
                opt++;

            switch (opt[0])
            {
                default:
                    printf("Unknown option '%s'.\n", opt);
                    goto exit;
            }
        }
        else
        {
            std::string tmp = std::string(arg);
            if (tmp.empty())
            {
                printf("ERROR: Invalid empty filename.\n");
                goto exit;
            }

            if (optInputFilename.empty())
                optInputFilename = tmp;
            else
            if (optOutputFilename.empty())
                optOutputFilename = tmp;
            else
            {
                printf("ERROR: Too many filenames specified.\n");
                goto exit;
            }
        }
    }

    if (optInputFilename.empty() || optOutputFilename.empty() || optShowHelp)
    {
        printf(
            "ply2bin - Convert ASCII PLY file to binary format PLY\n"
            "Usage: %s [options] <input.ply> <output.ply>\n"
            "-?            Show this help\n"
            "\n",
            argv[0]
            );

        goto exit;
    }

    if (!model.loadFromPLY(optInputFilename))
        goto exit;

    if ((outFile = fopen(optOutputFilename.c_str(), "wb")) == NULL)
    {
        printf("ERROR: Could not create output file.\n");
        goto exit;
    }

    printf("Writing output PLY ..\n");
    if (!dmFWriteBINPLY(outFile, model))
    {
        printf("ERROR: Error writing output PLY file.\n");
    }

exit:
    if (outFile != NULL)
        fclose(outFile);

    return 0;
}